Non-staining topical iodine composition and method

ABSTRACT

Non-staining topical iodine disinfecting compositions having the ability to inactivate pathogens associated with skin infections or diseases. based upon the presence of molecular iodine in a concentration above at least 15 ppm. Any other iodine species selected from the group consisting of complexed iodine and triiodide may be present with the total of such other iodine species limited to a concentration of less than about 700 ppm so that any visible stain resulting from the application of this composition on the skin will dissipate without leaving any visible skin coloration.

This application is a continuation-in-part of parent application U.S.Ser. No. 08/895,362 filed Jul. 16, 1997, now abandoned.

FIELD

This application describes a method of topically treating skin withiodine to kill pathogens in and on the epidermal surface of the skinwithout irritating the skin and without leaving a visable skindiscoloration and to non-staining topical iodine compositions thatprovide antimicrobial persistence for the disinfection of topicalpathogens and for treatment and/or prevention of skin infections anddiseases.

BACKGROUND OF INVENTION

Tincture of iodine was first used as a topical disinfectant in 1839.Tincture of iodine and subsequent iodine compositions, like Lugol'ssolution, are topical irritants that stain human skin. The invention ofpovidone iodine in 1956 (U.S. Pat. No. 2,739,922), commonly referred toas “tamed” iodine, eliminated the topical irritancy associated withiodine but not the staining.

Povidone iodine contains very low (1-10 ppm) concentrations of moleculariodine (I₂) and high concentrations of triiodide (I₃ ⁻≈10,000 ppm) andiodide (I⁻≈5,000 ppm). Such compositions are referred to as “complexed”iodine. Complexed iodine generically refers to compositions whereinmolecular iodine is complexed with organic molecules and/or iodide.Molecular iodine is complexed in order to increase shelf-life and reduceirritation. It is currently described in the literature and believed bythose skilled in the art that molecular iodine is the iodine speciesresponsible for epidermal irritancy and staining. By lowering theconcentration of molecular iodine it is believed that the irritancy andstaining of iodine is minimized.

Many inventions that rely upon complexed iodine have been made in thefield of topical iodine compositions. Iodine is complexed by contactinga source of diatomic iodine (I₂) with a polymeric material having largesegments of polymeric residues derived from ethylene oxide, propyleneoxide or other alkylene oxides in the form of block polymer chains.Examples include ethoxylated surfactants, cellulose, cellulosederivatives and polyvinyl pyrrolidone components. The alkoxylated(usually ethoxylated) surfactants include, but are not limited to, thegroup consisting of alkylphenol ethoxylates, ethoxylated fatty acids,alcohol ethoxylates, alcohol alkoxylates, polysorbates (ethoxylatedsorbitol) and ethylene oxide-propylene oxide copolymers (commonly calledPoloxamers as described in U.S. Pat. No. 5,368,868). A preferred sourceof iodine for reaction with nonionic materials to form iodine complexesis a composition comprising iodine in association with an inorganiciodide which provides a source of “active” iodine. Such a source isdescribed in Winicov, U.S. Pat. No. 3,028,299, Cantor et. al. U.S. Pat.No. 3,728,449, Schmidt W. et. al. U.S. Pat. No. 5,503,838, Brink et al.U.S. Pat. No. 5,173,291, and McKinzie M. et al., U.S. Pat. No.5,529,770. Commonly, at least 0.35 parts of iodide (I⁻) are present perpart of diatomic iodine.

Topical application of biocidal agents has been accomplished usingsolutions, ointments and physical appliances. To provide prolongedantisepsis, it is usually necessary to repeatedly apply an iodinetopical agent since microorganisms may survive the initial application.Topical iodine biocides are usually water soluble which leads to theirremoval from the epidermis by contact with water or bodily fluids.Increasing the water and bodily fluid resistance of topically appliediodine agents and thereby increasing the substantivity and length ofbactericidal activity has been a long-standing goal in the art. Thisinvention teaches against compositions that impart a highly visibleiodine coloration to the epidermis such as that derived from complexediodine and further discloses formulation constraints to provide apersistent non-irritating topical iodine disinfectant that does notstain. Such compositions have several commercially useful properties.The iodine compositions of this invention are not materially affected bywater and body fluids and provide long lasting efficacy. Also, thecompositions of this application provide iodine in a form that iscapable of penetrating the skin and inactivating pathogens that residewithin and on the skin.

SUMMARY OF THE INVENTION

The term “molecular iodine” as used herein refers to diatomic iodine,which is represented by the chemical symbol I₂, which is not complexedwith other molecules so that it is free to diffuse into epidermaltissue.

The term “complexed iodine” as used herein, refers to free moleculariodine that is combined with an organic carrier or with iodide anions toform triiodide such that the chemical activity of free molecular iodineis reduced. The complexed iodine is preferably prepared by combiningdiatomic iodine and a complexing agent.

The term “iodide anion” as used herein, refers to the species that isrepresented by the chemical symbol I⁻. Suitable counter-ions for theiodide anion include sodium potassium and the like.

The term “triiodide” as used herein, refers to the species which isrepresented by the chemical symbol I₃ ⁻. It is recognized by one skilledin the art that triiodide can dissociate into one iodide anion and onemolecule of free molecular iodine.

The term “total iodine” as used herein, refers to the following iodinespecies: free molecular iodine, iodide, organically complexed forms ofiodine and triiodide.

The term “rate of iodine generation” as used herein, refers to the rateat which molecular iodine is formed.

The term “ratio of molecular iodine” as used herein, refers to the ratioof molecular iodine (I₂) to other iodine species such as iodide andtriiodide.

It has been believed that molecular iodine is an irritant andresponsible for the staining of skin associated with the use of topicaliodine compositions. We have observed that complexed iodine, notmolecular iodine, is the species of iodine that is primarily responsiblefor skin staining in commercially available iodine compositions. We havefurther observed that it is possible to formulate compositions that willdeliver molecular iodine into the epidermis and not stain or irritateskin. Once molecular iodine penetrates into the skin, it maintains itsbiocidal activity while in the skin and can diffuse back out of the skin(W. Gottardi, Journal of Hospital Infection, Vol. 29, page 9, 1995).Such back-diffusion provides a long-lived chemical barrier that isresistant to water and body fluids.

This application describes the formulation constraints necessary toprovide a topical iodine disinfectant that will not irritate or stainepidermal tissue but will otherwise kill pathogens on the epidermis;these formulation constraints apply to the following forms of iodine:molecular iodine, iodide, triiodide and complexed iodine. The teachingsand examples in this application do not make any attempt to specificallyenumerate all of the prior art in the area of topical iodinepreparations. Excipients that are known to be compatible with complexediodine may also be of use with compositions and conditions described inthis application. Such excipients include surfactants, thickeners, filmforming agents, penetrants, humectants, emollients, dyes, skinconditioning agents, stabilizing agents, opacifiers, wetting agents,chelating agents, buffers, organic acids and fragrances.

DESCRIPTION

Topical disinfectants are used to inactivate pathogenic organisms thatare present on the epidermis and to prevent pathogenic organisms frompopulating the epidermis. A preferred topical disinfectant will (a) notirritate or stain the epidermis, (b) have a broad spectrum of activity,(c) rapidly inactivate pathogens, (d) provide residual activity for 2 to8 hours, (e) resist water and bodily fluids, and (f) prevent pathogenicorganisms from repopulating the epidermis. To date there are no perfecttopical antimicrobial compositions in commerce. The compositionsdescribed in this application are based on defined ratios of freemolecular iodine to total iodine and provide, in combination with otherexcipients, the basis for preferred topical disinfectants.

Iodine compositions, as compared to topical compositions based on otheractive agents, have a material disadvantage in that they stain skin.Typical iodine stains are reddish brown or yellowish in color and thesestains do not readily dissipate from the epidermis. It has long beenassumed that the form of iodine that stains the skin is moleculariodine. We have observed that this is not true and that most of thestaining from iodine compositions is due to triiodide as demonstrated inthe Examples of this application.

For purposes of this application, a stain is a yellowish-browncoloration of the skin that does not completely dissipate after adefined time period. The relevant time period for dissipation of a stainwill vary with the intended application. For instance, if a topicaldisinfectant is applied to the faces of adolescent girls several times aday, then any coloration that may be present should dissipate within 1minute. If a topical antifungal composition is formulated for use ontoes and applied prior to sleeping then any coloration should dissipatewithin 6 hours. If a topical iodine composition is formulated for use oncow teats to prevent mastitis and applied after milking then colorationcan remain for at least 30 minutes post application.

It is obvious to one skilled in the art that there is a wide variationbetween people with respect to the degree of staining their skin willexperience from iodine-based topicals. We have also observed that thedegree of staining is a function of the carrier that contains theiodine. For instance, isopropyl myristate, which facilitates thepenetration of agents into the epidermis, reduces the degree ofcoloration from free molecular iodine. Also, the degree of staining fromtopical iodine compositions that are liquids is a function of theapplication time. The longer a liquid is in contact with the epidermis,the more pronounced the staining.

The most preferred compositions anticipated by this application will notproduce any coloration of the epidermis. The preferred compositions ofthis application will produce a mild iodine coloration that isdissipated within 10 minutes. The range of compositions anticipated bythis application will produce an iodine-mediated coloration that isdissipated within 3 hours. It is recognized by one skilled in the artthat it may be useful for the compositions contemplated in thisapplication to temporarily impart a color. For instance, it may be ofuse to a surgeon to view a color on skin prior to opening an incision.Such a coloration provides evidence that the site is disinfected.

The concentration of molecular iodine contemplated in this applicationranges from 15 ppm up to 330 ppm within a pH range of 3.0 to 7.5. Thepreferred concentration of molecular iodine is from 25 ppm to 175 ppm.The most preferred concentration of molecular iodine is from 25 to 100ppm.

Numerous methods known in the art can be utilized to form moleculariodine. For in situ generation of iodine from iodide the most commonoxidants are active chlorine compounds and hydrogen peroxide. However,in the latter case a catalyst is necessary to speed up the formation ofiodine. Other iodine generating compounds have been used includingiodine pentoxide and tetraglycine hydroperiodide. Molecular iodine canalso be generated by dilution of formulations that contain complexediodine or by dissolution of elemental iodine as is done in severaldevices utilized for water disinfection.

Molecular iodine can be generated in situ in an aqueous medium bycombining a source of peroxidase, a source of hydrogen peroxide and aniodide. This combination is known to be bactericidal. This bactericidalactivity results from the enzymatic reaction that occurs whenperoxidase, hydrogen peroxide and iodide react in solution at acontrolled pH between pH 3.0 and 7.5. Peroxidase is known to effect thetransfer of electrons from iodide to hydrogen peroxide. Hydrogenperoxide is converted into water by this reaction. The preferred oxidantof this invention is hydrogen peroxide. Any material that acts as asource of hydrogen peroxide when admixed in an aqueous environment issuitable for this application. The term “source of peroxide” forpurposes of the present invention and as used herein shall mean anymaterial alone or in combination which can serve as precursors forhydrogen peroxide including metal peroxides, percarbonates,persulphates, perphosphates, peroxyesters, urea peroxide, peroxyacids,alkylperoxides, acylperoxides and perborates. Alternately methyl, ethyland other higher molecular weight peroxides can be used as a source ofhydrogen peroxide but these are not preferred. Mixtures of two or moreof these substances can also be used. The preferred concentration forhydrogen peroxide is between 0.001 and 0.1% in the final compositionprior to initiation of the oxidation of iodide.

Suitable dry sources of iodide anion include sodium iodide and potassiumiodide as well as other salts of iodide. Any compound that yields iodideanion upon dissolution in an aqueous environment is suitable for thisapplication. The simple salts of iodide are preferred and have theadvantage of being less costly. Additionally, they have a long shelflife in solid and liquid form.

The enzyme peroxidase is identified by the International Union ofBiochemistry and the International Union of Pure and Applied Chemistryby the Enzyme Commission identification No. E.C. 1.11.1.7 althoughcertain members of E.C. 1.11.1.8 can also be used. These classes ofperoxidase can be obtained from a wide variety of sources including milk(lactoperoxidase), soy bean, and human leukocytes (myerloperoxidase).Within these two E.C. classes the further requirement for a suitableperoxidase as defined in this application is that it is capable ofoxidizing iodide to iodine within the pH range of 3 to 7.5. The leastexpensive peroxidases suitable for this application is horseradishperoxidase and soybean peroxidase. It is anticipated that peroxidasethat has been cloned from either horseradish, milk or human leukocytesor other sources will be suitable as a source of peroxidase for thisapplication. Additionally, it has been observed that chemically modifiedperoxidase is suitable for use in this application. Modifications to theamino, carboxyl or carbohydrate moieties yield a suitable catalyticagent for inclusion in this application. The chemical modifications toperoxidase include cross-linking of enzyme molecules to each other, tosolid surfaces or to other proteins. The chemical agents used forcrosslinking include glutaraldehyde, maleimides, succinimides,carbodiimides, dicarboxylates, activated glycols, imidoesters,photoreactive azides and other agents known to one skilled in the art.

This application teaches that the concentration of triiodide should beminimized in order to minimize staining as demonstrated in the Examplesof this disclosure. It may be necessary to formulate a composition at aparticular pH and to incorporate certain additives that necessitate theincorporation of triiodide or promote the formation of triiodide. Inother words, it is not always possible to eliminate triiodide fromcompositions of matter that contain substantial concentrations ofmolecular iodine. However, in accordance with the present invention itis necessary to carefully maintain the concentration of triiodide atbelow a preferred maximum level in order to minimize staining.

The complexing of molecular iodine by iodide ion has long been of majorinterest, and studies of this subject have used solubility, distributionand potentiometric, conductimetric, and spectrophotometric techniques.As a result, the factors that govern the formation of triiodide are wellknown in the art. In 1965, Ramette and Sandford (Journal of the AmericanChemical Society, Vol. 87(22), pages 5001-5) published a study, hereinincorporated by reference, that provides an analysis of the factors thatgovern the formation of triiodide in addition to an empirical algorithmthat accurately predicts the concentration of triiodide under a varietyof conditions. As a practical matter, it is very useful to measure theconcentration of molecular iodine as well as the concentration oftriiodide and to correlate these measurements with the total mass ofiodine known to be present in a composition.

The concentration of triiodide contemplated in this application rangesfrom 0 ppm up to a maximum of 700 ppm. The preferred concentration oftriiodide should range from 0 ppm to 100 ppm. The most preferredconcentration of triiodide should range from 0 to 50 ppm.

Complexed forms of iodine (e.g., polyvinylpyrrolidone iodine) other thantriiodide can also stain skin. It is well known that 10%polyvinylpyrrolidone iodine forms a film on skin when it dries and thatthis film is highly colored. When the compositions of this inventionalso contain a complexed form of iodine, the sum of the concentrationsof iodine complexed with organic compounds and triiodide should belimited to a maximum not to exceed 700 ppm under any circumstances.Iodide does not cause staining of skin. The concentration of iodide isnot a critical aspect of staining but it will effect the concentrationof molecular iodine and triiodide.

The types of compositions contemplated under this application includeliquids, gels, creams, ointments and emulsions. The type of compositionis not a determinative aspect of this application rather the absoluteand relative concentration of molecular iodine and complexed iodine arethe two most critical aspects of this invention. Examples of thedifferent types of compositions are provided, by way of example, in theExamples section of this application. It is clear from these experimentsthat many different types of compositions are compatible with theteachings of this application.

Dermatological compositions frequently form a film over the epidermis.Such a film can provide added physical protection and serve to increasethe emolliency of the topical composition. A good film-formingcomposition should be dermatologically acceptable and capable ofapplication conveniently in a water based mixture which dries quickly onskin. The film should be water and body fluid resistant and permitfacile transmission of water vapor. The film should adhere suitably toepidermis and be capable of facile removal from said epidermis. The filmshould be soluble in a dermatologically acceptable solvent such as wateror a lower alkyl alcohol which may be used as or in a remover solutionwhich could be employed to remove the film when desired. The filmcontemplated in this application is, when dry, about 0.002 mm to 0.05 mmthick.

The surfactants useful in the context of this application includeanionic surfactants such as carboxylate, sulfonate, and sulfatematerials including carboxylate surfactants such as potassiumalkyloxycarboxylates, an alkyl sarcosinates, alkyl benzene sulfonates,alpha olefin sulfonates, and sulfonates with an ester amide or etherlinkage. Additionally useful surfactant agents include sulfated alcohol,sulfated alcohol ethoxylates, sulfated alkyl phenols, sulfatedcarboxylic acid amides and esters, sulfated natural oils and fats aswell as agents such as dioctyl ester sodium sulfosuccinic acid.

The thickeners useful in the context of the invention are preferablytaken from the group consisting of alkyl celluloses, the alkoxycelluloses, xanthan gum, guar gum, polyorgano sulfonic acid and mixturesthereof. The thickeners are chosen based on compatibility with the otherformulation ingredients and desired viscosity. Generally speaking thethickener should be present at a level of from about 0.01-10% by weight,and more preferable from about 0. 1-1% by weight.

The penetrants useful in the context of the invention include isopropylmyristate, polyethylene glycol, and propylene glycol. Generally speakingthe penetrant should be present at a level of from about 0.1 to 4% byweight.

Generally, any dispersible skin conditioning agent, humectants andemollients, known to those of skilled in this art may be used in thepresent invention. Preferred emollients to be used in the invention aretaken from the group consisting of glycerin, propylene glycol, sorbitol,lanolin, lanolin derivatives, polyethylene glycol, aloe vera, GlucamateDOE 120 (a polyethoxylated glucose dioleate containing 120 ethoxy unitsin the polyethylene glycol moiety, available), Glucam E10 (apolyethoxylated methyl glucose containing 10 ethoxy units), Glucam E-20(a polyethoxylated methyl glucose containing 20 ethoxy units in thepolyethylene glycol moiety), Glucam P-10 (a polyethoxylated methylglucose), Glucam P-20 (a polyethoxylated methyl glucose containing 20propoxy units in the polyethylene glycol moiety), allantoin, alginates,monoester salts of sulfosuccinates, alphahydroxy fatty acids, esters offatty acids, ceramides, and mixtures thereof. Broadly, the conditioningagents are used at a level of from about 0.5-20% by weight. The mostpreferred conditioning agents are mineral oil, glycerin and/or propyleneglycol, and are usually employed at a level of from about 1-20% byweight, and more preferably from about 2-10% by weight.

Dye or pigment used in the compositions of the invention may be anyorganic or inorganic dye or pigment which is a chemically acceptabletrace constituent on epidermal surfaces. Generally, dyes which areuseful in the composition of this invention include 7 FD&C dyesavailable that are generally recognized as safe. Although any number ofcolorants may be used, these dyes are preferred due to their relativeacceptability in various solid and liquid food systems. Generally, dyesor pigments used in the invention are present in a concentration rangingfrom about 0.001 to about 0.01 wt %.

Chelating agents or sequestrants can be useful stabilizing agents in theinvention particularly when a complexed form of iodine is present.Commonly available chelating agents can be used in the inventionincluding both inorganic and organic chelating agents. Organic chelatingagents include alkyl diamine polyacetic acid, chelating agents such asEDTA (ethylenediamine tetracetic acid tetrasodium salt), acrylic acidand polyacrylic acid type stabilizing agents, phosphonic acid andphosphonate type chelating agents and others. Preferable organicsequestants include phosphonic acids and phosphonate salts including1-hydroxy ethylidene-1, 1-diphosphonic acid, amino [tri(methylenephosphonic acid)], ethylene diamine [tetra(methylene-phosphonic acid)],2-phosphonobutane-1,2,4-tricarboxylic acid as well as alkali metalsalts, ammonium salts, or alkyl or alkanol amine salts including mono-,di- or triethanol amino salts. Inorganic chelating agents includecommonly available polyphosphate materials such as sodium pyrophosphate,sodium or potassium tripolyphosphate along with cyclic or higherpolyphosphate species. Preferably, such a sequestering agent is used ata concentration ranging from about 0.05 wt % to about 0.5 wt % of thecomposition.

Commonly available organic acids that can be used in the inventioninclude benzoic acid, mandelic acid, sorbic acid, citric acid, loweralkanoic acids and their food-grade salts, such as the sodium potassiumor ammonium salts thereof. These organic acids, their salts, or mixturesthereof are present in the composition in an amount between about 0.010to 0.5 percent by weight, preferably from 0.050 to 0.20 percent byweight. The presently preferred organic acids are mandelic acid, benzoicacid and sorbic acid, with benzoic acid suitably present as sodiumbenzoate and sorbic acid suitably present as the free acid. Each ofthese acids, or their salts, and others, alone or in combinations, canbe incorporated into the compositions contemplated in this invention.

Commonly available film forming agents that can be used in the inventioninclude polyvinylpyrrolidone (PVP), PVP derivatives like alkylated PVP,PVP copolymers likePVP/dimethylaminoethylmethacrylate/polycarbamyl/polyglycol ester,Polaxomers, polyethylene glycol, polyvinyl alcohol, polysulfonic acid,water soluble cellulose derivatives, acrylate copolymers such asacrylate/hydroxyester acrylate copolymers, collagen and collagenderivatives, keratin, polyquaternium compounds, interpenetratingpolymers of polycrylic acid and a block terpolymer of propylene oxideand ethylene oxide with reverse thermal gelation properties, polyvinylmethacrylate derivatives and tosamide epoxy resins.

Various formulations anticipated under the teachings of this applicationmay require two separate phases or components. This is understood and itis incorporated into the teachings of this application. Two componentsproducts that are activated prior to use by admixture are commonlyavailable. Cheeseborough Pond's USA Company (CPUSA) has successfullyintroduced Mentadent© toothpaste. Consequently, CPUSA has commercializeda mouthwash and handcream that both rely upon admixture prior to use. Inmany instances, pharmacists compound a product and package it into adispenser for subsequent use by the consumer. It is anticipated thatmany of the potential formulations contemplated under this applicationwill fall into such a category.

Any method to generate molecular iodine, in situ, may be used toformulate a dermatological non-staining topical iodine antimicrobialcomposition in accordance with the present invention including themethod of generating molecular iodine taught in copending patentapplication Ser. No. 08/960,149 filed Oct. 29, 1997, U.S. Pat. No.5,885,592, the disclosure of which is herein incorporated by reference.As taught in the foregoing patent application molecular iodine may begenerated, in situ, by combining an iodine reductant in concert with anoxidant iodine species having a positive oxidation state and a bufferingagent for causing oxidation-reduction reactions to occur in which theiodine reductant is reduced to molecular iodine or in which the oxidantiodide species is oxidized into molecular iodine. The iodine reductantmay be selected from the group consisting of iodide, sodium thiosulfate,ascorbate, lactose, reducing sugars and imidazole whereas the oxidantiodine species may be selected from the group consisting of hydrogenperoxide, iodate, alkali salts of peroxide such as calcium peroxide,peroxidase, ascorbic acid and/or other pharmaceutically acceptableorganic acids with an oxidation potential greater than −0.54 electronvolts. The preferred formulation combines an iodide and an iodate with asuitable buffer to control pH preferably in two phases with the firstphase incorporating the iodate and iodide in a first buffer to form abasic pH and with the second phase being the activator phase which ishighly buffered with an acidic buffer such as, for example, citric acid,phosphoric acid and phthallic acid. The iodide in the preferredformulation may be selected from the group consisting of sodium iodide,potassium iodide, ammonium iodide, calcium iodide, and magnesium iodideand the iodate of such formulation may be selected from the groupconsisting of calcium iodate, magnesium iodate, potassium iodate, andsodium iodate. The preferred range of the iodide to iodate species inthe preferred formulation is from {fraction (1/3+L )} to {fraction(1/12+L )}. The pH of the iodate/iodide phase should be no less than 8.0and preferably greater than 8.5. The iodate/iodide phase can assume adiverse range of compositions: liquid, gel, ointment or cream. Thecritical aspect of the iodate/iodide phase is that these two activeagents are stable. Prior to use, the iodate/iodide phase is combinedwith a second activator phase. The activator phase is highly buffered ata pH that is less than 5.0. The pH of the mixture of these two phasesmust be controlled such that the final pH is 5.0 or less. As aconsequence of altering the pH environment, molecular iodine isgenerated from the iodate and iodide. An example of such a compositionis given in Example 12 below.

The following examples are illustrative of the teachings of thisapplication and are not meant to limit the invention in any manner.

EXAMPLES

1. This experiment was performed to demonstrate that molecular iodinedoes not necessarily stain human skin and when it does impart color toepidermal tissue, it does so in a rapidly reversible manner. Elementaliodine was weighed on an analytical balance and dissolved in one literof water that had been acidified with 2 drops of 0.1N hydrochloric acid.The concentration of molecular iodine in the water was confirmed bypotentiometric analysis (Gottardi, W., 1983. Fresenius Z. Anal. Chem.,Vol. 314, pages 582-585). Samples were also titrated with thiosulfate todetermine that at least 95% of the theoretical yield of titratableiodine was in the form of molecular iodine as opposed to triiodide. Theconcentration of molecular iodine was varied from 25 ppm to 330 ppm.

One dram vials (Kimble catalog # 60931) were used to deliver 4 mL of theroom temperature iodine solutions samples. The vials were placed on theforearm of a subject and then the forearm was inverted to initiatecontact of the sample with the iodine solution. The contact area was acircle with a diameter of 1.3 cm. The samples were held on the arm for30 seconds at room temperature. Three different subjects were used forthis experiment. Immediately after the 30 second contact time the armsof the subjects were examined for stains; 10 minutes after the end ofthe contact time all subjects arms were examined for stains again. Theresults of these experiments are shown in Table 1 below and demonstratethat molecular iodine does not stain skin irreversibly.

For the purposes of this application, two different parameters were usedto characterize the color and intensity of the term stain. The hue ofthe color imparted to skin was characterized by using the Pantone ColorMatching System (Pantone Color Specifier, Pantone Inc., Carlstadt, N.J.)which allows comparison with 1,012 defined colors on two types of paper.Stains from triiodide were matched to the Pantone color chip No. 152C.Short-lived coloration from molecular iodine were matched to the Pantonecolor chip 1 375C.

TABLE 1 Coloration of Human Skin by a 30 Second Exposure to MolecularIodine Concentration 25 ppm 50 ppm 100 ppm 200 ppm 300 ppm Min. postcontact 0 10 0 10 0 10 0 10 0 10 Subject 1 N N N N N N S N S N Subject 2N N N N L N S N S L Subject 3 N N N N L N S N S L Key to Table 1. N = novisible staining L = light staining barely noticeable S = a clearlyvisible coloration

The intensity of any coloration on skin was characterized by applying anaqueous solution of known concentrations of a food dye, Brown No. 3(Crompton & Knowles, Mahwah, N.J.—Code DP935159), for 10 seconds usingthe method described above for application of iodine. Brown No. 3 wasapplied to the skin at concentrations that ranged from 500 ppm to 30 ppmand the intensity of the color from Brown No. 3 was compared to theintensity of coloration from iodine compositions. For instance, theintensity of color 10 minutes after a 30 second contact with a 600 ppmaqueous triiodide solution was equivalent to the color from a 10 secondexposure to a 250 ppm Brown No. 3 solution. In contrast, the intensityof color 10 minutes after a 30 second contact with a 300 ppm aqueousmolecular iodine solution was equivalent to the color from a ten secondexposure to a 30 ppm Brown No. 3 solution which is barely discernible.

2. Three samples from Example 1 were used to confirm that moleculariodine will penetrate into skin and remain in the skin for a prolongedtime period.

Application of the iodine solution onto skin was performed as describedin Example 1 above with the exception that the contacted area wasflushed with water for 15 seconds immediately after following contactbetween the iodine solution and skin. The method of Gottardi (J. Hosp.Infect., 1995, Vol 29, pages 9-18) were used to measure the amount ofmolecular iodine coming out of the skin. Briefly, 1 mL of adiethyl-p-phenylenediamine (DPD) solution was placed concentrically ontothe exposed area of skin and left there for 30 seconds. This solutionwas then transferred to a 1 cm cuvette and the absorbance was read at553 nm. Control values were obtained by contacting the DPD solution toan unexposed area on the forearm of each subject. Control values weresubtracted from the experimental measurements. Iodine solutionscontaining 50 ppm, 150 ppm and 300 ppm of molecular iodine were used forthis example. Two measurements were made (one measurement of eachforearm) at each iodine concentration on all three subjects. The averagereading from all three subjects is shown in Table 2 as a function oftime

TABLE 2 Diffusion of Iodine from Skin Post Application Time (minutes)after application of iodine 3 6 20 60 90 120 240 660 Mean 0.06 0.17 0.190.18 0.13 0.08 0.06 0.02 absorbance 8 4 2 6 1 3 6 9 50 ppm I₂ Mean 0.320.31 0.48 0.53 0.50 0.46 0.36 0.20 absorbance 7 1 7 3 1 2 9 4 150 ppm I₂Mean 0.78 0.65 1.11 0.93 0.77 0.64 0.57 0.40 absorbance 4 0 5 1 5 3 9 8300 ppm I₂

The conclusion from this experiment is clear. Molecular iodine maintainschemical activity on and in the skin even under conditions where thereis no skin coloration from molecular iodine.

3. This experiment was performed to demonstrate that triiodide stainsepidermal tissue in a manner that is not rapidly reversible. Solutionsof triiodide were prepared by dissolving elemental iodine intooxygen-free solutions of sodium iodide that were at a pH of 4.5. A molarexcess of iodide was used. Based on thiosulfate titrations,potentiometric measurements of iodine and ion selective electrodemeasurements of iodide ion, essentially all of the elemental iodine wasconverted into triiodide. Solutions of triiodide were made that variedfrom 100 to 25,000 ppm. Four mL of each sample was transferred to a 1.0dram vial (Kimble catalog #60931) at room temperature and placed on theforearm of a subject and then the forearm was inverted to initiatecontact of the sample with the triiodide solution. The samples were heldon the arm for 10 seconds.

The contact areas were checked for stains at 10 minutes and 3 hoursafter exposure. A definite coloration of the epidermis was evident 3hours after contact with triiodide at concentrations from 25,000 to 700ppm. At 700 ppm triiodide the degree of color was minimally discernable.At 100 ppm triiodide staining was present at three hours but it was notvisibly noticeable.

4. This experiment was performed to demonstrate the relative stainingproperties of compositions that contain different concentrations andratios of molecular iodine/triiodide. Dilutions of strong Lugol'ssolution were made and characterized. Iodide ion was measured using aniodide ion selective electrode, molecular iodine was measured using thepotentiometric method of Gottardi and thiosulfate titrations were usedto calculate the concentration of triiodide. Four mL of each sample wastransferred to a one-dram vial at room temperature and placed on theforearm of a subject and then the forearm was inverted to initiatecontact of the sample with the triiodide solution. The samples were heldon the arm for 10 seconds. Observations were made of the contacted areaat 10 seconds and three hours.

Table 4 below shows the results of these experiments. The data indicatesthat there are preferred ranges for both molecular iodine and triiodide.Controlling the concentrations of these species within those ranges canyield compositions that provide defined levels of staining.

TABLE 4 Staining of Human Skin by Various Concentrations and Ratios ofMolecular Iodine to Triiodide (10 second exposure) Molecular IodideIodine Triiodide Observation ppm ppm ppm pH Dark stain present longer25,670 103 11,929 6.12 than 3 hours. Dark stain present longer 15,122123 6,980 6.08 than 3 hours. Dark stain present longer 10,684 154 4,6955.74 than 3 hours. Easily visible stain present 5,782 162 2,411 5.54longer than 3 hours. Some coloration at three 1,452 124 508 5.32 hours.No staining at 10 seconds. 224 56 51 5.01

5. This experiment was performed to demonstrate that molecular iodinethat diffuses into the skin can inactivate pathogens that are on or inthe skin. A saturated solution of molecular iodine was prepared at a pHof 4.5. The concentration of molecular iodine was measured to be 320 ppmand the concentration of triiodide was determined to be less than 5 ppm.A 1.0 dram vial containing four mL of the saturated iodine solution wascontacted with the forearm of a subject and then the forearm wasinverted to initiate contact of the sample with the molecular iodinesolution. The samples were contacted with the arm for 30 seconds. Aftercontact the treated arm was flushed with water for 15 seconds and dried.

Six circular skin areas on two different subjects that were treated withthe saturated iodine solution were marked immediately after treatmentwith a water-resistant ink. Two hours after contact each area wasinoculated with 25 mL of a 1:100 dilution of a 48 hour soy-trypticaseculture of Staphylococcus aureus. Ninety minutes after inoculation themouths of sterile 25 mL flasks filled with 2 mL of soy-trypticase with2% Tween 80 were placed over the marked skin areas. The flasks weregently shaken for 1 minute and a colony count was performed on bloodagar plates after incubation at 37° C. for 48 hours. The residualbiocidal effect from skin associated molecular iodine was determined bysubtracting the log of the colony counts from the areas of skin thatwere contacted with iodine from the controls (log colony count fromuntreated skin). The average difference in colony counts between treatedand untreated skin was 2.4 logs. Efficacy was also demonstrated whenthis experiment was repeated using Staphylococcus epidermidis,Streptococcus agalactica, Candida albicans, Salmonella typhimurium, andPseudomonas aeruginosa. The smallest log reduction was observed withPseudomonas aeruginosa and was equal to 0.5 logs. When a solution thatcontained 700 ppm of triiodide, but no molecular iodine, was used inthis experiment, no measurable reduction in the concentration ofpathogens was observed.

This experiment demonstrates that non-staining iodine can serve as anefficacious biocide on the skin surface for a prolonged time period.That is to say, it is evident from this experiment that a sufficientdegree of kill on and in the epidermis is achieved from the use ofmolecular iodine as described this application. This experimentdemonstrates that molecular iodine works independent of triiodideconsistent with previous observations in the art (U.S. Pat. No.5,419,902; U.S. application Ser. No. 08/293,283, U.S. Pat. No.5,629,024; U.S. application Ser. No. 08/551,478, U.S. Pat. No.5,639,481; U.S. application Ser. No. 08/684,334, U.S. Pat. No.5,648,075) which are incorporated herein.

6. This experiment was performed to demonstrate that the inventiondescribed in this application is compatible with an oil/water emulsion.The raw materials included in this mineral oil emulsion are shown inTable 6. The materials for this composition were selected without anyconsideration or optimization of the materials with respect to theindividual components used. It is reasonably expected by one skilled inthe art that this composition is representative of a broad class ofoil/water emulsions which are incorporated herein. It was decided toformulate a highly emollient dermatological composition for thetreatment of bacterial infections of the skin. The formulation and theprocedure to make this creamy emulsion is shown below.

TABLE 6 Raw Materials in Cream Emulsion Composition Percent by NumberWeight Material Chemical Name 1 75.0 DI Water Water 1 0.3 Liposorb L-20Polysorbate-20 1 0.1 Natrosol 250H HR Hydroxyethylcellulose 2 15Petrolatum Petrolatum 2 3.5 Mineral Oil 130 Mineral Oil 130 2 0.3Lanette O Cetearyl Alcohol 2 3.7 Brij 72 Steareth-2 2 2.2 Myverol 18-04Hydrogenated Palm Glyceride

The procedure to make the emulsion follows: heat the water inComposition #1 to 76° C. and slowly add Natrosol, disperse the Natrosolthoroughly then add the Liposorb L-20 under propeller mixing. Mix theraw materials in Composition #2 and then heat to 78° C. Slowly addComposition #2 at 78° C. to Composition #1 at 76° C. under homogenizermixing. Homogenize for 5-10 minutes or until emulsification is complete.Remove the homogenizer and allow the mixture to cool to 25° C. underpropeller mixing.

This base composition was used to prepare two separate components thatyield molecular iodine when combined. Horseradish peroxidase and iodidewere mixed with the cream in one compartment and hydrogen peroxide wasplaced in a second compartment. The cream (75 grams) was mixed with H₂O₂so that the final concentration of hydrogen peroxide was 0.6%.Peroxidase and sodium iodide were mixed in a 3/1 ratio and 2.5 grams ofthis mixture was combined with 97.5 grams of the cream. Five mL of thecream containing hydrogen peroxide and five mL of the cream containingperoxidase/iodide were mixed and the concentration of total iodine wasdetermined to be 720 ppm. The concentration of sequestered iodine,including triiodide, was 500 ppm and the concentration of moleculariodine was approximately 220 ppm.

Immediately after mixing the two components, 0.5 mL of the mixture wasimmediately applied to a square 2 inch section of the forearm of threehuman subjects. The DPD method to detect iodine out-gassing described inExample 2 was used to confirm that iodine was associated with the areaof skin that had been treated with the cream. Iodine was detectedimmediately after sample application and at 1, 3 and 6 hours posttreatment; at 1 hour the DPD absorbance was 0.624, at 3 hours it was0.403, and at 6 hours it was 0.286.

7. A topical gel composition was developed to determine the rate ofpenetration of molecular iodine into skin. Several different carrierswere evaluated to determine their ability to deliver iodine into skin.These carriers are Carbopol 941 (1%), polysulfonic acid (7.5% PSA),hydroxypropyl methyl cellulose (5% HPC or Methosil), carboxymethylcellulose (1% CMC), sodium alginate (2%) and Sepigel 305 (3%). As aninitial screen the relative rate of disappearance of iodine from theseformulations into skin was evaluated visually. A known amount of aformulation was placed on the top of a subject's hand and spread into athin layer. After one minute, a known amount of this sample was removedand assayed for iodine content. Two vehicles, PSA and CMC, showed rapiddisappearance of iodine. The disappearance of iodine is due to iodinepenetration into the skin since the control (i.e., a formulation spreadover a glass slide) showed no loss of iodine over the same time period.

The hydroxypropyl methyl cellulose gel was formulated to deliverdifferent concentrations of iodine. The four different gel compositionsthat were prepared contained concentrations of total iodine that variedbetween 140 to 500 ppm. The gels were contacted to the forearm of theidentical volunteer and iodine out-gassing was measured 5 minutes aftercontact. The results are shown below: three mL of each formulation wascontacted with and rubbed into the forearm of human subjects and theirskin was observed for staining. No staining was observed in anyinstance. Iodine out-gassing was measured for each concentration ofiodine in the Methosil gel using the method described in Example 6. Theresults of these measurements are shown below in Table 7. Iodine clearlyentered into the skin and was back-diffusing out of the skin.

TABLE 7 Iodine Determination from Skin 5 Minutes Post Treatment with HPCGels Total Iodine 140 250 400 500 (ppm) Absorbance 0.306 0.395 0.6370.945 (DPD)

8. A viscous barrier teat dip was formulated using the conditionsdescribed in this application. The teat dip was formulated in twoseparate liquid components. One component contained lactoperoxidase andiodide. The other component contained hydrogen peroxide. When the twocomponents were mixed in equal volumes 300 ppm of total iodine wasgenerated with 200 ppm of molecular iodine being formed. The fullyactivated teat dip contained 0.4% polyvinyl pyrrolidone, 10% glycerin,2% benzoic acid, 2% polyethylene glycol, 0.2% xanthan gum, 0.03% sodiumlauryl sulfate, 0.01% silicone antifoam, 0.1% mixture of three food dyesand 3% Rheothick 80-11. The composition had a relatively high viscosityand provided significant film-forming capability with resultantprotective properties.

9. The rate of healing wound was measured using Yorkshire pigs, weighingapproximately 20 k. The pigs, were allowed to acclimate for 1 weekbefore 50 to 100 shallow wounds measuring 7 mm wide and 10 mm long by0.3 mm deep were made in the paravertebral and thoracic areas with anelectric dermatome. The wounds were treated daily for the duration ofthe study with normal saline or a solution of iodine. Three times daily,1.0 mL of these iodine solutions were applied to the wound sites andheld there by an occlusive bandage. Beginning on day 4 after woundingand each day thereafter, 5 to 6 wounds and the surrounding normal skinwere excised, and harvested specimens were incubated with 0.5 molarsodium bromide at 37° C. for 24 hours, and then the epidermis wasseparated from the dermis. The epidermal sheet was examined for defects.Wounds were considered healed if there were no defects in the epidermis,and wounds were considered not to be healed if there were one or moredefects.

The two iodine compositions were generated by oxidizing iodide withhorseradish peroxidase and hydrogen peroxide. The compositions containedeither 47 or 175 ppm of free molecular iodine and the correspondingconcentration of thiosulfate titratable iodine was 102 and 280 ppmrespectively. The percentage of healed wounds was determined postwounding from day 4 to 7. By day 8, 100% of the wounds were healed inall three treatment groups. There was not a material difference in therate of wound healing among the three treatment groups at day 7 as shownbelow.

TABLE 9 Percentage of Wounds Healed versus Time Free % Wounds HealedMolecular Titratable Molecular Day After Wounding Iodine (ppm) Iodine(ppm) Iodine (ppm) 5 6 7 8 3.14 × 10⁻³ 280 175 0 0 50 100 1.26 × 10⁻³102 47 0 0 50 100 0 (Saline) 0 0 0 0 71 100

10. The cream described in Example 7 above was used to treat the skindisease caused by Propionibacterium acnes. Prior to administration ofthe cream, quantitative bacteriologic cultures were obtained from thecheeks (two test sites) of four male subjects with acne. After one weekof treatment cultures were again taken. An area of 3.9 cm² were outlinedby holding a sterile glass cylinder (diameter 2.23 cm) against the skin.The cheeks of subjects were cleansed by wiping for 30 seconds with asterile gauze soaked with 0.1% Triton X-100 to remove surface debris andbacteria. Wash solution (1.0 mL of 0.1% Tween-80 in 0.075 molarphosphate buffer, pH 7.9) was pipetted into the cylinder and each areascrubbed with moderate pressure for 1 minute using a sterile Teflonstir-bar. The wash fluid was aspirated, replaced with 1.0 mL of freshwash solution, and the scrub repeated. The two 1.0 mL samples werecombined and diluted serially in 0.05% buffered Tween-80 on Schadleragar and cultured anaerobically for 7 days. P. acnes were identified bycolony morphology and susceptibility to P. acnes bacteriophage.

The number of P. acnes bacteria per square centimeter was calculatedfrom plate counts and expressed as a logarithm. Subjects applied creamto their cheeks three times daily. The difference between the initiallevel of P. acnes and the level after one week of treatment wasexpressed as the log reduction in counts. The mean value of P. acnes atthe start of the study was 6.18 or 1.51×10⁶ cfu/cm². The mean valueafter one week of treatment was 4.12 which equals a log reduction of P.acnes of 2.06.

11. The 300 ppm samples of molecular iodine described in Example 1 wasused to confirm that molecular iodine will penetrate into skin andpermeate into the skin to provide sub dermal tissue penetration.

Application of the iodine solution onto skin was performed as describedin Example 1 above with two exceptions: (1) the contacted area wasflushed with water for 15 seconds immediately after following contactbetween the iodine solution and skin and (2) the sample was applied tothe skin once every 2 hours over a six hour time period (4applications).

Twenty-four hour urine samples were collected on three subjects for theday immediately prior to the experiment. Twenty-four hour urine sampleswere collected on three subjects on the day of the experiment. The urinesamples were analyzed to determine their total iodine content. Urinaryconcentrations of total iodide were measured by utilizing thereduction-oxidation reaction between ceric ioni and arsenite ioncatalyzed by iodide. The concentration of iodide in the sample istherefore proportional to its catalytic activity. Samples along withstandards and controls in a urine matrix were first digested withchloric acid. Arsenious acid was added, the samples were transferred toan autoanalyzer, ceric ammonium sulfate was added “on line” and theoptical transmission was measured spectrophometrically at 420 nm. Thereagents used were: perchloric acid (HCIO₄), 70%-72%, ACS grade;sulfuric acid (H₂SO₄), ACS grade; arsenic trioxide (AS₂0₃), ACS grade;sodium chromate (Na₂CrO₄), ACS grade; potassium chlorate (KCIO₃),purified; ceric ammonium sulfate (NH₄)₄Co(SO₄)₄-2H₂O; sodium chloride(NaCl), ACS grade; potassium iodate; and distilled water. 200 μL ofsample, 200 μL of a Low control and 100 μL of the High control weretransferred into appropriately numbered tubes. 1.0 mL of a 0.02, 0.04,and 0.06 μg/mL iodate standards were transferred into appropriatelynumbered tubes. Nothing was added to the 0.0 μg/mL tube. 3.0 mL of a 28%chloric acid solution was added to each tube. Samples, controls, andstandards were incubated at 105° C.-110° C. using a sand bath heater.Digestion was completed in approximately 2-2.5 hours. The end point ofthe digestion was the formation of chromium trioxide crystals (redcrystals). Samples were allowed to cool to room temperature. 2.1 mL ofarsenious acid solution was added to each tube and mix. Approximately2.0 mL of each processed sample was added to autoanalyzer cups (2 mLvolume) and they were placed on the sampler. Prior to allowing thesamples to proceed through the autoanalyzer system for the colorreaction, a screen test on the left over portion of the test sample wasperformed in order to determine if a sample contained a grossly elevatediodine content. This was done to avoid contamination of the autoanalyzersystem. The screen test is performed by adding 1 drop of the cericammonium sufate reagent to each tube. If the yellow color fades tocolorless (clear) within 1.5 minutes, the iodine content is too high tobe measured. These high samples were removed from the sampler anddiscarded. They were then repeated on further dilution. After thescreening procedure was completed, the samples were run through theautoanalyzer at a sampling rate of 40 samples per hour with thetemperature controlled water bath set at 32° C.±0.1° C. The %transmission was recorded and the concentration of iodine in each samplewas determined by comparison to the standards.

TABLE 11 Sub Dermal Penetration of Iodine as Measured by Iodine Analysisof Urine 24 Hour Urine (ug iodine) Prior to I₂ Application Post I₂Application Subject 1 95 647 Subject 2 114 846 Subject 3 106 741

The conclusion from this experiment is clear. Molecular iodine maintainschemical activity on the surface of skin even under conditions wherethere is no skin coloration from molecular iodine.

12. A gel formulation was prepared that delivered 200 ppm of moleculariodine when activated. This composition was prepared using a Carbopolgel (type 980) as the gelling agent. The components used to generatemolecular iodine were iodide and iodate. Iodide and iodate wereformulated into a single gel phase. A second buffer gel phase wasformulated such that upon admixture of an equal volume of the two phases(iodide/iodate phase; buffer phase), 200 ppm of molecular iodine wasformed. The rate of formation of molecular iodine was monitored and theformulation was intended to form 200 ppm of molecular iodine within 60seconds after admixture.

The iodide/iodate phase contained the following components: Carbopol 980at 1.00%; EDTA at 0.10%; glycerin at 10%; boric acid at 0.10%; 1.4%sodium hydroxide; 0.06% sodium iodide; and 0.20% sodium iodate. The pHof this gel phase was adjusted to 10.3. The buffer phase container thefollowing chemicals: 4% Carbopol 980; 12% citric acid; 0.10% EDTA; 10%glycerin; and 0.10% boric acid.

An equal volume of the two gels was mixed and the amount of moleculariodine was measured at 0, 30, 60, 90 and 150 seconds. Molecular iodinewas measured by extraction of the molecular iodine into chloroform andsubsequent measurement of the visible absorbance at 520 nm. The percentconversion of iodide into molecular iodine (i.e., yield) was determinedand is reported the table below.

Formation of molecular Iodine in Carbopol 980 versus Time

Min. I₂ ppm I₂ Yield 0 0 0 0.5 205 67 1 204 66 1.5 202 66 2.5 215 70.5

Fifty mL of each gel phase was mixed in a glass flask and a ground glassstopper was placed in the top of the flask to prevent loss of moleculariodine to the atmosphere. The concentration of molecular iodine wasmeasured in this sample at day 1, 3, 7, 14 and 21. This study wasperformed to demonstrate that the compositions of this application candemonstrate stability after being activated. The results of thesemeasurements are shown in the table below.

Molecular Iodine versus Time in Carbopol Gel Day 0.04 3 7 14 21 Numberppm I₂ 212 204 223 205 198

What is claimed is:
 1. A method of topically treating skin withoutirritating the skin and without leaving a visible skin discolorationnoticeable to the naked eye after a duration not exceeding three hourscomprising the step of, applying an iodine composition to the surface ofthe skin, said iodine composition comprising molecular iodine in aconcentration above at least 15 ppm and at least one other iodinespecies selected from the group consisting of triiodide and complexediodine and wherein the total concentration of the triiodide componentpresent in the iodine composition is less than about 700 ppm.
 2. Amethod as defined in claim 1 wherein said molecular iodine is present ina range of from 15 ppm to 330 ppm.
 3. A method as defined in claim 2wherein said molecular iodine is present in a range of from 25 ppm to175 ppm.
 4. A method as defined in claim 1 wherein said duration doesnot exceed 10 minutes.
 5. A method as defined in claim 2 wherein saidmolecular iodine is generated in situ.
 6. A method as defined in claim 5wherein said molecular iodine is generated using an aqueous compositionconsisting essentially of a source of peroxidase, a source of hydrogenperoxide, an iodide and a buffer to control the pH of the compositionbetween a pH of 4.0 and 7.5.
 7. A method as defined in claim 6 for thetreatment of fungal and viral infections of the skin wherein said iodinecomposition further comprises an anionic surfactant selected from thegroup consisting of carboxylate, sulfonate, a carboxylate surfactant, analkyl sarcosinate, alkyl benzene sulfonate, alpha olefin sulfonate and asulfonate with an ester amide or ether linkage.
 8. A method as definedin claim 7 wherein said iodine composition further comprises dispersibleskin conditioning agents selected from the group consisting of filmforming agents, penetrants, organic acids, humectants and emollients. 9.A method as defined in claim 7 wherein said iodine composition furthercomprises a sequestering agent.
 10. A method as defined in claim 8wherein said emollient is selected from the group consisting ofglycerin, propylene glycol, sorbitol, lanolin, polyethylene glycol, aloevera, Glucamate DOE 120 (a polyethoxylated glucose dioleate containing120 ethoxy units in the polyethylene glycol moiety, available), GlucamE10 (a polyethoxylated methyl glucose containing 10 ethoxy units),Glucam E-20 (a polyethoxylated methyl glucose containing 20 ethoxy unitsin the polyethylene glycol moiety), Glucam P-10 (a polyethoxylatedmethyl glucose), Glucam P-20 (a polyethoxylated methyl glucosecontaining 20 propoxy units in the polyethylene glycol moiety),allantoin, alginates, monoester salts of sulfosuccinates, alphahydroxyfatty acids, esters of fatty acids, ceramides, and mixtures thereof. 11.A method as defined in claim 8 wherein said organic acids are selectedfrom the group consisting of benzoic acid, mandelic acid, sorbic acid,citric acid, lower alkanoic acids and sodium, potassium or ammoniumsalts thereof.
 12. A method defined in claim 8 wherein said film formingagents are selected from the group consisting of: polyvinylpyrrolidone(PVP), alkylated PVP,PVP/dimethylaminoethylmethacrylate/polycarbamyl/polyglycol ester,polaxomers, polyethylene glycol, polyvinyl alcohol, polysulfonic acid,water soluble cellulose, acrylate/hydroxyester acrylate copolymers,collagen and collagen derivatives, keratin, polyquaternium compounds,interpenetrating polymers of polyacrylic acid and a block terpolymer ofpropylene oxide and ethylene oxide with reverse thermal gelationproperties, polyvinyl methacrylate derivatives and tosamide epoxyresins.
 13. A method as defined in claim 2 wherein the iodinecomposition applied to the skin is within a pH range of 3.0 to 7.5. 14.A method as defined in claim 13 wherein the triodide concentration isless than about 100 ppm.
 15. A method as defined in claim 14 for thetreatment of fungal and viral infections of the skin wherein said iodinecomposition further comprises an anionic surfactant selected from thegroup consisting of carboxylate, sulfonate, a carboxylate surfactant, analkyl sarcosinate, alkyl benzene sulfonate, alpha olefin sulfonate and asulfonate with an ester amide or ether linkage.